undefined Terms smashville247.net Topical outline  Geometry overview  MathBits" Teacher sources Terms the Use call Person: Donna Roberts
In geometry, formal definitions are developed using other characterized words or terms. There are, however, 3 words in geometry that are not formally defined. This words room point, line and plane, and are referred to as the "three undefined terms of geometry".
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While this words room "undefined" in the formal sense, we have the right to still "describe" this words. The descriptions, declared below, describe these words in relationship to geometry.
POINT • a allude indicates a place (or position) in space. • a allude has no dimension (actual size). • a suggest has no length, no width, and also no elevation (thickness). • a point is usually named with a capital letter. • in the coordinate plane, a allude is named by an notified pair, (x,y). while we stand for a suggest with a dot, the dot can be really tiny or an extremely large. Remember, a allude has no size. The dimension of the dot drawn to stand for a point makes no difference. Points have no size. They merely represent a location. LINE (straight line) • a line has actually no thickness. • a line"s size extends in one dimension. • a line goes top top forever in both directions. • a line has actually infinite length, zero width, and also zero height. • a line is assumed to be straight. • a heat is drawn with arrow head on both ends. • a line is called by a single lowercase manuscript letter, or by any type of two (or more) points which lie top top the line. Lines have the right to be labeled v a single script letter, or by two points ~ above the line, . The thickness that a line provides no difference. See more: Is It Illegal To Back Out Of Your Driveway ? Is It Illegal To Back Out Onto A Main Road PLANE • a plane has 2 dimensions. • a aircraft forms a level surface expanding indefinitely in all directions. • a plane has infinite length, boundless width and zero elevation (thickness). • a plane is attracted as a foursided figure resembling a table or a parallelogram. • a aircraft is named by a solitary letter (plane m) or by 3 coplanar, yet noncollinear,* point out (plane ABC). airplane m or airplane ABC. When the diagram of a plane has edges, you should remember that the plane actually has no boundaries. * upright points room points that lie on the same straight line. Coplanar points space points that line in the very same plane.
